csv_parser.py

# Dawsin Blanchard, Sam Braga, Brian Couture, and Ethan Trott
# COS226 University of Maine

import csv, hashlib

# this variable allows us to limit the number of rows we parse
# (for convenience in debugging)
row_limit = -1

# returns the total number of rows in the file
def count_lines(filename):
    with open(filename, "r") as csvfile:
        return sum(1 for row in csvfile) - 1

# this will yield each Plate ID within our row_limit when iterated over
def get_plates(filename):
    with open(filename, "r") as csvfile:
        datareader = csv.reader(csvfile)
        count = -1
        for row in datareader:
            if (count == -1):
                #ignore the header row
                count += 1
            elif (row_limit == -1 or count < row_limit):
                yield row[1]
                count += 1
            else:
                return

#creates the SHA256 hashes of the plates and saves them to hashes.csv
def create_hashes(filename):
    hashes = []
    with open('hashes.csv', 'w') as file:
        for plate in get_plates(filename):
            #get the sha256 hash of the value
            hash = hashlib.sha256(str(plate).encode('utf-8'))
            #store the hash in the list
            hashes.append(hash.hexdigest())
            #write the hash to the file
            file.write(hash.hexdigest()+"\n")
    return hashes

def load_hashes():
    f = open("hashes.csv", "r")
    if (row_limit > 0):
        return f.readlines(row_limit*65)
    else:
        return f.readlines()